I'm a photographer and I don’t like scheduling people by email, because it usually goes something like this:
Them: Hi, I'd like to make an appointment, what's your availability?
Me: (I check my personal calendar and my studio calendar.) My schedule changes frequently but I currently have Tues at 10am, and Wed at 2pm available. Also, I need to know how much studio time you want, and I also need your phone number in order to book the time.
Them: (A few hours later.) Oh, I work during the day, do you have anything on evenings or weekends?
Me: (I check my personal calendar and my studio calendar again.) I have Tues evening and Sat morning available. I still need to know how much studio time you want, and I also need your phone number in order to book the time.
Them: (A few hours later.) Oh, I bowl on Tuesdays. Where are you located?
Me: You’ll find directions on my web site.
Them: (A few hours later.) I’m not sure I can make it that early on a Saturday. Do you have anything on Sunday?
Me: I need to know how much studio time you need before I can say when I’m available.
Them: (A few hours later.) Oh, I just want the budget package with the half hour of studio time.
Me: (I check my personal calendar and my studio calendar again.) I normally take Sundays off, but I can do that if that’s your only available day. How about 3pm?
Them: (A few hours later.) Could you do noon?
Me: I usually have brunch with a friend on Sundays, but I can do that if it’s your only time. I still need more info. (see above)
Them: (A day later.) Oh, I don’t want you to miss your brunch! How about 6:30pm?
Me: (I check my personal calendar and my studio calendar again.) I’m sorry, since you last replied, someone else has booked that time. How about 8pm?
Them: (A few hours later.) Perfect! What should I wear for my portrait? Do you take Visa?
Me: Great. Yes, I take all forms of payment, and you’ll find tips on what to wear on my web site. I still need your phone number.
Them: Oh, sorry. My phone is 555-1212.
This could have been accomplished with a 2-minute phone call rather than a long back and forth e-mail exchange. This is why doctors and dentists don’t schedule by email. Can you imagine if they tried to schedule all of their clients via email? This is why email is the wrong tool (and the phone is the right tool) for scheduling appointments.
If I can't use the phone, I request that people send the following info in their email:
1. phone number
2. how much time they need
3. at least three blocks of time when they're available
4. respond quickly since my schedule changes frequently
Another option for getting the above information is to use a form on your web site with different fields for phone, blocks of time, etc. The fields act as gentle reminders for them to provide the information.
Make this your policy and save yourself time and hassle. And it makes you look efficient too.
But be cautious, because you don't want the tone of your e-mail response to be harsh or off-putting to your new client. Make them glad they chose you.